H740P IT mode

[TheUsD]

Maybe I just did a really bad search but I could not find out any info on Flashing a Dell PERC 740H to IT mode. Was looking at purchasing an R740XD 24-port (bay).

I'm also open to any other card that would work for this chassis for latest TrueNAS build.

 

[jgreco]

There is no "IT mode" for a PERC H740P. You'll be tempted to believe that it has a "HBA mode" next, which Dell says it does, but it is not what we're looking for. You don't want a shitty RAID-card-lobotomized-into-sort-of-an-HBA setup. It's like taking a Lamborghini, putting a speed governor on it, and calling it a pickup truck because it can't go faster than 50MPH. Doesn't make it a pickup truck. Just gives you the crappiness of both worlds.

See

What's all the noise about HBAs, and why can't I use a RAID controller?

1) An HBA is a Host Bus Adapter. This is a controller that allows SAS and SATA devices to be attached to, and communicate directly with, a server. RAID controllers typically aggregate several disks into a Virtual Disk abstraction of some sort...

www.truenas.com

You can use something like a Dell HBA330, which I haven't seen firsthand but people say is just an LSI 3008. You should probably also be able to use any other LSI 3008 card. I don't have firsthand experience with the R740XD though. There are several discussions on these forums that should be relevant.

 

[TheUsD]

There is no "IT mode" for a PERC H740P. You'll be tempted to believe that it has a "HBA mode" next, which Dell says it does, but it is not what we're looking for.

I wasn't really tempted but wanted to confirm before purchasing. When it comes to PERCs, I don't trust Dell having accurate information.

You can use something like a Dell HBA330

I was looking at those but from my experience with the R720 16 bay, you have to have two PERCs, the mini and the full because two SAS cables are shortened for the mini and the other two are for the full in the RISER. I can't seem to find any good internal PICs of the 740XD to determine how many SAS cables there are, how many SAS ports are needed, what lengths the cables are, for a stock device.

The rest of the post I'm aware of but always, thanks for the refresher.

 

[jgreco]

I wasn't really tempted but wanted to confirm before purchasing. When it comes to PERCs, I don't trust Dell having accurate information.

The H740P's a lovely controller, by the way, just not for ZFS.